Lithia-based materials are promising cathodes based on an anionic (oxygen) redox reaction for lithium ion batteries due to their high capacity and stable cyclic performance. In this study, the properties of a lithia-based cathode activated by Li2RuO3 were characterized. Ru-based oxides are expected to act as good catalysts because they can play a role in stabilizing the anion redox reaction. Their high electronic conductivity is also attractive because it can compensate for the low conductivity of lithia. The lithia/Li2RuO3 nanocomposites show stable cyclic performance until a capacity limit of 500 mAh g−1 is reached, which is below the theoretical capacity (897 mAh g−1) but superior to other lithia-based cathodes. In the XPS analysis, while the Ru 3d peaks in the spectra barely changed, peroxo-like (O2)n− species reversibly formed and dissociated during cycling. This clearly confirms that the capacity of the lithia/Li2RuO3 nanocomposites can mostly be attributed to the anionic (oxygen) redox reaction.

in this study, we used tris(trimethylsilyl)borate (tMSB) as an electrolyte additive and analysed its effect on the electrochemical performance of lithia-based (Lithia/Li 2 Ruo 3) cathodes. our investigation revealed that the addition of TMSB modified the interfacial reactions between a lithia-based cathode and an electrolyte composed of the carbonate solvents and the Lipf 6 salt. the decomposition of the Lipf 6 salt and the formation of Li 2 co 3 and-CO 2 was successfully reduced through the use of tMSB as an electrolyte additive. it is inferred that the protective layer derived from the tMSB suppressed the undesirable side reaction associated with the electrolyte and superoxides (oor o 0.5-) formed in the cathode structure during the charging process. this led to the reduction of superoxide loss through side reactions, which contributed to the increased available capacity of the Lithia/Li 2 Ruo 3 cathode with the addition of tMSB. the suppression of undesirable side reactions also decreased the thickness of the interfacial layer, reducing the impedance value of the cells and stabilising the cyclic performance of the lithia-based cathode. This confirmed that the addition of TMSB was an effective approach for the improvement of the electrochemical performance of cells containing lithia-based cathodes. One of the most important issues relating to lithium-ion batteries (LIBs) is the development of new cathodes with higher energy densities than commercially used LiCoO 2 , Li(Ni, Co, Mn)O 2 (NCM), and Li(Ni, Co, Al)O 2 (NCA) 1-7. Fundamentally, the capacity of most cathodes can be attributed to the cationic redox of transition metals such as Co, Ni, and Mn in the structure. Therefore, it is necessary to increase the amount of transition metals (per weight or volume) in the cathode structure to improve its energy density, which is not an easy task considering the crystal structure of transition metal oxides. However, if the redox reaction of the anions (such as oxygen ions) can contribute to the capacity of the cathode, this problem can be overcome. The anions are much lighter than general transition ions, therefore the cathodes can provide much higher capacity (per weight) and energy density compared to cases relying on only cationic redox reactions. Subsequently, cathodes based on anionic redox reactions have been attractive research topics of late. As promising new cathode materials, Li-Nb-Mn-O, Li-Mn-O, and Li-RuM -O (M = Sn, Nb) have been studied for years 8-13. These materials have shown high capacity-up to approximately 300 mA•g −1 based on anionic redox associated with oxygen as well as cationic redox related to transition metals. However, their sluggish kinetics and structural instability have resulted in an inferior rate capacity and cyclic performance compared to commercial cathodes 8-13. Lithia (Li 2 O)-based materials are also one of the new candidates for high-capacity cathodes based on anionic redox reactions 14-20. In fact, most of the new cathodes such as Li-Nb-Mn-O, Li-Mn-O, and Li-RuM -O (M = Sn, Nb)...

The rare earth oxide wastes consisting of major 8 nuclides Y, La, Ce, Pr, Nd, Sm, Eu and Gd, are generated during the salt waste treatment of PyroGreen process. The final form of the rare earth is generated as the oxide state. In this study, six candidate glasses were developed to evaluate the feasibility for vitrifying the rare earth oxide wastes within the borosilicate glass system. The solubilities of the mixture of the rare earth oxide waste showed less than 25wt% at 1,200 ℃ , less than 30wt% at 1,300 ℃ , respectively. It means that solubility is increased with the temperature increment. The liquidus temperature of the homogeneous glass with 20wt% waste loading was determined as less than 950 ℃ . In more than solubility of rare earth oxides glass, formation of rare earth-oxide-silicate crystal in glass-ceramic occurred as the secondary phase. As their viscosity at melting temperature 1,200~1,300 ℃ was less than 100 poise, electrical conductivity was higher than 1 S/cm, 20~25wt% waste loading glasses with good surface homogeneity are judged to have good operability in cold crucible induction melter. Other physicochemical properties of the developed glasses are going to be experimented in the future.

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